assertNull(CrawlingParameterUtil.getCrawlerContext());

        // Create and set a CrawlerContext
        CrawlerContext context = new CrawlerContext();
        context.setSessionId("test-context-session");

        CrawlingParameterUtil.setCrawlerContext(context);

        // Verify it can be retrieved
        CrawlerContext retrieved = CrawlingParameterUtil.getCrawlerContext();
        assertNotNull(retrieved);

        final UrlQueue<?> urlQueue = objs.length > 1 && objs[1] instanceof UrlQueue<?> ? (UrlQueue<?>) objs[1] : null;
        try {
            final CrawlerContext crawlerContext = (CrawlerContext) objs[0];
            final Throwable e = (Throwable) objs[2];

            storeFailureUrl(crawlerContext, urlQueue, e.getClass().getCanonicalName(), e);
        } catch (final ContainerNotAvailableException e) {
            if (logger.isDebugEnabled()) {

        fileTransformer.setPath(file.getAbsolutePath());
        crawler.addUrl(url);
        crawler.crawlerContext.setMaxThreadCheckCount(3);
        // crawler.crawlerContext.setMaxAccessCount(maxCount);
        crawler.crawlerContext.setNumOfThread(numOfThread);
        crawler.crawlerContext.setMaxDepth(1);
        crawler.urlFilter.addInclude(url + ".*");
        final String sessionId = crawler.execute();

        // CrawlerContext crawlerContext = (CrawlerContext) objs[0];
    }

    /**
     * Processes no URL in queue log events.
     *
     * @param objs the log objects (should contain UrlQueue and thread check count)
     */
    protected void processNoUrlInQueue(final Object... objs) {
        // CrawlerContext crawlerContext = (CrawlerContext) objs[0];

            // num of threads
            final CrawlerContext crawlerContext = crawler.getCrawlerContext();
            final int numOfThread =
                    webConfig.getNumOfThread() != null ? webConfig.getNumOfThread() : Constants.DEFAULT_NUM_OF_THREAD_FOR_WEB;
            crawlerContext.setNumOfThread(numOfThread);

            // depth

                    crawlerContext.getNumOfThread(), crawlerContext.maxDepth, crawlerContext.maxAccessCount);
        }

        // context
        crawlerContext.urlFilter = urlFilter;
        crawlerContext.ruleManager = ruleManager;
        crawlerContext.intervalController = intervalController;

        super.setUp();

        crawlerThread = new CrawlerThread();
        crawlerContext = new CrawlerContext();
        crawlerContext.sessionId = "test-session";
        crawlerContext.numOfThread = 1;
        crawlerContext.maxThreadCheckCount = 10;
        crawlerContext.maxDepth = 3;
        crawlerContext.maxAccessCount = 0;

        urlQueueService = mock(UrlQueueService.class);

     * Otherwise, the provided {@code crawlerContext} is set in the thread-local storage.
     *
     * @param crawlerContext the {@link CrawlerContext} to be set for the current thread, or {@code null} to remove the context.
     */
    public static void setCrawlerContext(final CrawlerContext crawlerContext) {
        if (crawlerContext == null) {

void cleanup(String sessionId)  // Clean up session
void stop()                     // Stop gracefully
```

**Key Fields**: `crawlerContext`, `urlFilter`, `intervalController`, `clientFactory`, `ruleManager`

### CrawlerContext (`CrawlerContext.java`)

Execution context and configuration.

**Important Fields**:
```java
String sessionId                // Format: yyyyMMddHHmmssSSS

                    log(logHelper, LogType.NOT_MODIFIED, crawlerContext, urlQueue);

                    responseData.setExecutionTime(systemHelper.getCurrentTimeAsLong() - startTime);
                    responseData.setParentUrl(urlQueue.getParentUrl());
                    responseData.setSessionId(crawlerContext.getSessionId());